In addition, utilization of 4-ABS as sole nitrogen source was examined by growing mutants in PB medium with 3 mM of 4-ABS and gluconate. After 5 days of incubation with shaking at 150 r.p.m., growth was quantified by measuring A600 nm. Cells were grown in PBN medium supplemented with 5 mM of gluconate and 4-ABS. Samples were withdrawn every 48 h, filter sterilized and stored at

−20 °C click here for subsequent analysis. For thin layer chromatography (TLC) analysis, 7.5 μL of sample was spotted onto a C18 RP TLC plate (Merck). The plate was allowed to dry and developed in mobile phase of butanol–propanol–acetic acid–water at 8 : 4 : 1 : 1 (Feigel & Knackmuss, 1988). HPLC analysis was performed using Waters 600 equipped with a 4.6 × 250 mm Zorbax SB-Aq column (Agilent, Santa Clara, CA). The mobile phase consisted of 98% water, 1% methanol and 1% phosphoric acid (85%) at a flow rate of 1.0 mL min−1. Detection was carried out at 230 nm. 4-Sulfocatechol standard was synthesized according to published method (Saito & Kawabata, 2006). Chromogenic detection of diphenolic intermediate in catabolism of 4-ABS was done by growing cells on nutrient agar

supplemented with 50 μg mL−1p-toluidine and 0.5 mM FeCl3 (Parke, 1992). To complement RK40, the DNA region spanning phthalate dioxygenase-like gene and its putative promoter was amplified from wild-type PBC with Etofibrate primers PDOF 5′-TACTTGCCGGTCTCGTTCG-3′ and PDOR 5′-GTTCGGGGGTGTGCAGTC-3′, cloned into pGEM-T Easy vector (Promega) and this website subcloned as an EcoRI fragment into pBBR1MCS-5 (Kovach et al., 1995) to give pHG5. A similar approach was applied to RK32 complementation using primers DEHF 5′-GTTGAGACGCTCGTTGACC-3′ and DEHR 5′-TTTGCCTGAGAAATGTGTCG-3′ to amplify the ORFs of transposase and putative dehydrogenase to give pHG6. Plasmids were transformed into mutants via electroporation. Oxygen uptake was measured using a Clark-type oxygen electrode (YSI 5905, Yellow Springs Instruments). Cells

were pregrown in 20 mL NB medium, harvested by centrifugation and grown in 50 mL 0.5 × NB medium with 5 mM 4-ABS for 36 h to induce 4-aminobenzenesulfonate 3,4-dioxygenase activity. Cells were then harvested, washed twice with 25 mM potassium phosphate buffer, pH 7.0, and resuspended in the same buffer containing 1 mM 4-ABS (OD600 nm of 0.15–0.2). Oxygen uptake was measured polarographically at 30 °C for 2 h. DNA sequences of insertion site in RK1, RK23, RK32 and RK40 were deposited in EMBL Nucleotide Sequence Database and assigned accession numbers FR720595, FR720597, FR720598 and FR720599, respectively. From three different electroporation experiments, approximately 10 000 kanamycin-resistant colonies were obtained, representing an average transformation efficiency of 1.7 × 105 CFU μg−1 transposon.

Many LGBT (lesbian, gay, bisexual and transgender) people fear stigma, homonegativity and discrimination from health care providers [5]. These factors

discourage persons from sexual minorities from seeking and receiving essential HIV prevention, testing, care and treatment services, condemning them to remain at disproportionately Atezolizumab high risk of HIV acquisition [6]. Greater access to testing and availability of prevention and care services for persons infected with HIV can reduce new infections and lead to reductions in HIV-associated morbidity and mortality [7]. To overcome some of these barriers to the early diagnosis and linkage to care of infected persons, the patient-based organization Projecte dels NOMS-Hispanosida created in 2006 BCN Checkpoint, a community-based centre (CBC) for MSM in the gay area of Barcelona. Tanespimycin mouse This centre offers HIV testing free of prejudice, peer counselling and support, and linkage to medical care for people diagnosed with HIV infection. The centre is staffed by a part-time physician, a nurse, 12 counsellors, a receptionist and two administrative assistants. All members of the team are gay, some are HIV positive and six counsellors are part-time volunteers. Peer support is fundamental in helping HIV-infected persons to deal with the emotional impact of receiving such a diagnosis, as well as in helping them to seek medical care Phosphoglycerate kinase and adhere to treatment.

This CBC is dedicated to MSM because Barcelona has a significant MSM community with a high prevalence of HIV infection (17%) [8]. Awareness of serostatus also results in a reduction in the risk of transmission of HIV to sex partners, as a substantial proportion of PLWHIV reduce sexual behaviours likely to transmit HIV after discovering that they have HIV infection [9]. Thus, HIV testing represents secondary prevention for people who know their HIV status (reduction

of prevalence and severity of the disease) and primary prevention for the community (reduction of HIV incidence). Projecte dels NOMS-Hispanosida, in addition to setting up BCN Checkpoint, started promoting regular testing for MSM and implemented for the first time in Spain the rapid HIV test in CBCs. As a result of this implementation, the average increase in the number of HIV tests performed in the CBC network in Catalonia was 102.9%, and this increase reached 275.9% in BCN Checkpoint, as described by Fernàndez-López et al. [10] The aim of this study was to assess the efficiency of BCN Checkpoint in detecting new cases of HIV infection and efficiently linking newly diagnosed individuals to care. BCN Checkpoint offers free, anonymous and confidential HIV voluntary counselling and testing (VCT), syphilis VCT, other sexually transmitted infection (STI) counselling services for MSM, and vaccination against hepatitis A and B.

Many LGBT (lesbian, gay, bisexual and transgender) people fear stigma, homonegativity and discrimination from health care providers [5]. These factors

discourage persons from sexual minorities from seeking and receiving essential HIV prevention, testing, care and treatment services, condemning them to remain at disproportionately see more high risk of HIV acquisition [6]. Greater access to testing and availability of prevention and care services for persons infected with HIV can reduce new infections and lead to reductions in HIV-associated morbidity and mortality [7]. To overcome some of these barriers to the early diagnosis and linkage to care of infected persons, the patient-based organization Projecte dels NOMS-Hispanosida created in 2006 BCN Checkpoint, a community-based centre (CBC) for MSM in the gay area of Barcelona. find more This centre offers HIV testing free of prejudice, peer counselling and support, and linkage to medical care for people diagnosed with HIV infection. The centre is staffed by a part-time physician, a nurse, 12 counsellors, a receptionist and two administrative assistants. All members of the team are gay, some are HIV positive and six counsellors are part-time volunteers. Peer support is fundamental in helping HIV-infected persons to deal with the emotional impact of receiving such a diagnosis, as well as in helping them to seek medical care Fenbendazole and adhere to treatment.

This CBC is dedicated to MSM because Barcelona has a significant MSM community with a high prevalence of HIV infection (17%) [8]. Awareness of serostatus also results in a reduction in the risk of transmission of HIV to sex partners, as a substantial proportion of PLWHIV reduce sexual behaviours likely to transmit HIV after discovering that they have HIV infection [9]. Thus, HIV testing represents secondary prevention for people who know their HIV status (reduction

of prevalence and severity of the disease) and primary prevention for the community (reduction of HIV incidence). Projecte dels NOMS-Hispanosida, in addition to setting up BCN Checkpoint, started promoting regular testing for MSM and implemented for the first time in Spain the rapid HIV test in CBCs. As a result of this implementation, the average increase in the number of HIV tests performed in the CBC network in Catalonia was 102.9%, and this increase reached 275.9% in BCN Checkpoint, as described by Fernàndez-López et al. [10] The aim of this study was to assess the efficiency of BCN Checkpoint in detecting new cases of HIV infection and efficiently linking newly diagnosed individuals to care. BCN Checkpoint offers free, anonymous and confidential HIV voluntary counselling and testing (VCT), syphilis VCT, other sexually transmitted infection (STI) counselling services for MSM, and vaccination against hepatitis A and B.

, 1998). The sequences

were analyzed for the presence of secretion signal sequences using SignalP (ver. 3.0; http://www.cbs.dtu.dk/services/SignalP/) with the hidden Markov model (Bendtsen et al., 2004) and for protein localization using Psort (ver. 1; http://psort.hgc.jp/form.html; Horton et al., 2007). Phylogenetic trees were constructed using mega (ver. 4; Tamura et al., 2007) with the neighbor-joining method and Poisson correction model. A comparison of synonymous and nonsynonymous nucleotide substitution rates is a Erlotinib molecular weight useful approach for studying the mechanisms of DNA sequence evolution. The numbers of nonsynonymous and synonymous substitutions per site (dN and dS, respectively) and their ratio (dN/dS) are important indicators of selection pressure at the protein level; dN/dS values of <1, 1, and >1 imply stabilizing selection, neutral mutations, and diversifying PD-1 antibody positive selection, respectively.

To examine positive selection pressure on dnaD, imp, and idpA of PoiBI, we used ClustalW (Thompson et al., 1994) to align the nucleotide sequences of dnaD, imp, and idpA of PoiBI and WX (Liefting & Kirkpatrick, 2003; GenBank Acc. No. AF533231). Alignments were adjusted manually, and dN/dS values were calculated as the overall average of the codon sites in each gene with Jukes-Cantor model of Nei-Gojobori method by mega (ver. 4; Tamura et al., 2007). A significant difference test for dN/dS was performed according to a previously described procedure (Messier & Stewart, 1997). For expression cloning, the entire imp gene from the Primelo Jingle Bells PoiBI isolate was PCR-amplified Non-specific serine/threonine protein kinase using primers impful-F and imp-R (Table S1), and a truncated form of the gene was PCR-amplified

using primers impout-F and imp-R (Table S1). The truncated gene was designed to encode an Imp derivative lacking the N-terminal transmembrane region. Similarly, the entire idpA gene from the Primelo Jingle Bells PoiBI isolate was PCR-amplified using primers idpAful-F and idpAful-R, and a truncated form of the gene idpA gene was PCR-amplified using primers idpAcent-F and idpAcent-R. The truncated gene was designed to encode an IdpA derivative lacking both transmembrane regions and containing only the hydrophilic domain. In addition, idpA gene fragments encoding the N- and C-terminal halves of the IdpA hydrophilic domain were amplified using the primer pairs idpAcent-F/idpA534-R and idpA532-F/idpAcent-R, respectively. A pET system (Novagen) was used to fuse histidine-tag (His-tag) and express the full-length and truncated Imp and IdpA proteins, as well as the IdpA hydrophilic fragments, in Escherichia coli. Each of the six PCR products described above was doubly digested with NdeI and XhoI and inserted into pET30a(+), thereby placing a His-tag at the C-terminus of the cloned fragments. The resulting constructs were transformed into E.

The substrate specificity of the AT domains in the PKSs was predicted using the web server sbspks (Anand et al., 2010). The fosmid sequences were deposited at NCBI under the accession numbers JN121120–JN121124. Fungal mycelia were harvested from an 8-day PDA liquid culture by ultracentrifugation at 10 000 g for 15 min. The mycelia were kept at −80 °C before RNA extraction. The total GDC 0199 RNA was isolated from 100 mg of frozen mycelia using the TRIzol reagent (Invitrogen) and was then treated with an RNeasy MinElute Cleanup kit (Qiagen GmbH, Hilden, Germany). The primers were designed on the exon regions in the fosmid sequences (Table S1). The quantitative real-time PCR (qPCR) was performed

using the Mx3000P™ Real-Time PCR System (Stratagene, Waldbronn, Germany). The 25-μL qPCR reactions contained 5 ng RNA, 0.1 μm primers and

1× Verso™ 1-Step QPCR SYBR Green Mix (ABgene Ltd, Epsom, UK). The thermal cycling conditions were as follows: 50 °C for 15 min; 95 °C for 15 min; followed by 40 cycles of 15 s at 95 °C, 30 s at 55 °C and 30 s at 72 °C; and 95 °C for 30 s, 60 °C for 30 s, and 95 °C for 30 s for the dissociation curve analyses. The elongation factor 1α genes (tef1) of C. militaris (Liu et al., 2009) and Cordyceps ninchukispora strain BCC 26678 obtained from NCBI (Table S2) were used for normalizing the gene expression in strains 1630 and DSM 1153, respectively. The expression level of the target genes (ER) was expressed as A colony radial growth assay was performed by Succinyl-CoA inoculating Smoothened Agonist in vivo 3 μL spore suspension (1 × 105 spores mL−1) on a sterilized filter paper disk placed in the center of a PDA plate. Images were taken after a 15-day growth at 20 °C in the dark. For microscopic observation, cultures were prepared by inoculating

a small amount of mycelia on a 1-cm3 PDA block placed on a microscopic slide (Stevens, 1981). The blocks were then covered with a coverslip and incubated at 20 °C. After removing the slab, the mycelia on the coverslip were fixed with Carnoy’s fixative and observed using a Zeiss Axioskop microscope (Carl Zeiss, Germany). To compare the biochemical signatures of the two strains, the growth medium and mycelia from 300 mL liquid culture were extracted with acetyl acetate and chloroform/acetone (1 : 1, v/v) and analyzed using high-pressure liquid chromatography (HPLC) coupled with mass spectrometry (MS). Details are provided in the electronic Supporting Information. The internal transcribed spacer (ITS) of the nuclear ribosomal DNA sequences from the two Cordyceps strains was amplified by PCR using the primers listed in Table S1. The sequences were deposited at NCBI with accession numbers JN121119 and JN121122. The reference sequences were downloaded from NCBI (Table S2). A phylogenetic tree was constructed with Bayesian Inference using the beast v1.6.1 package (Drummond & Rambaut, 2007).

, 2007); thus, C. divergens has not always been considered as important in terms of spoilage potential, SP600125 cost indeed the potential of species belonging to the Carnobacterium genus as spoilage agents is not always clear-cut. There are studies that even propose C. divergens as biopreservative agent (Spanggaard et al., 2001; Laursen et al., 2005; Ringo et al., 2007; Kim & Austin, 2008). Several studies were focusing on the shift of the microbiota during the process of meat deterioration (Borch et al., 1996; Gram et al., 2002; Ercolini et al., 2006; Schirmer et al., 2009). A shift from aerobic Gram-negative Pseudomonas

spp. to Gram-positive LAB was observed during this process of pork meat spoilage (Schirmer et al., 2009; Jiang et al., 2010). Other studies have revealed a LAB-dominating microbiota, including Lactobacillus spp. and Leuconostoc spp. in spoiled meat products (Borch et al., 1996; Bjorkroth & Korkeala, 1997; Bjorkroth et al., 2000; Santos et al., 2005; Chenoll et al., 2007), indicating an overgrowth of the fresh meat

dominating Carnobacterium this website spp. by other LAB during storage (Jones, 2004; Chenoll et al., 2007). But at the time of packaging, the concentration of these LAB were below the detection threshold of culturing methods of bacteria. This could be a plausible explanation why we did not dominantly isolate species of the genera Lactobacillaceae. In contrast to earlier observations, where L. sakei was mainly detected in psychrotrophic bacterial

flora of vacuum-packed meat and meat products (Hugas, 1998; Jiang et al., 2010), we have isolated L. sakei in our study out of in air-packaged fresh meat juice samples but not out of juice samples of VP meat. The literature is controversial about the benefit of LAB in raw meat. In one respect, RVX-208 these bacteria are discussed as causative agents of meat deterioration (Borch et al., 1996; Labadie, 1999; Koutsoumanis et al., 2006), and on the other hand, several studies have shown the importance of LAB in the microbiota of fresh meat (Hastings et al., 1994; Gill, 1996). There it is supposed that LAB compete with other spoilage-related bacteria only in fresh meat under VP or MAP by releasing metabolites such as organic acids (e.g. lactate) and bacteriocins, thus preventing the growth of spoilage bacteria and, therefore, increasing the shelf life of the fresh meat and meat products. Our data reveal C. divergens as a dominating bacterium in fresh pork meat juice, whereas under continuous storage, Ercolini et al. demonstrated some species of the genus Pseudomonas as dominating active bacterial contributors to spoilage under aerobic conditions and even at refrigeration temperatures (Labadie, 1999; Ercolini et al., 2006, 2011; Koutsoumanis et al., 2006). In our study, Pseudomonas fluorescens were detected in 4/10 pork meat juice samples at moderate concentrations, supporting this observation. Besides other species, Pennacchia et al.

As an index of corticospinal excitability, we recorded MEP amplitudes from an intrinsic muscle of the hand contralateral to the stimulated hemisphere. Larger MEPs following presentation of Self than Other hands in the right but not the left hemisphere would be taken as evidence of right hemispheric specialization for self body-parts processing. Twelve right-handed healthy participants (eight female; age range 24–36 years, mean 29 years) with no history of previous neurological or psychiatric disease participated in the experiment after providing informed consent. They were naïve as to the purpose of the study, which was approved by the INSERM Ethics Board

and run in accordance to the Declaration of Helsinki. Stimuli were colour pictures of participants’ left hand (see Fig. 1) and mobile phone. ALK inhibitor cancer Flash photographs were taken with a digital camera before the experimental session. Eleven subjects owned their mobile phone for more than 1 year, whereas one subject owned his mobile phone for 3 months. Pictures were taken in an indirectly illuminated environment while standing against a black uniform background. Images were

equalized for visual properties such a brightness and contrast and digitally edited with Adobe Photoshop to reduce any visual dissimilarity, such as brightness and contrast. Ulixertinib In each trial, two stimuli from the same category (e.g. two hands or two mobile phones, 50% of trials for each category) were successively presented, and could either belong to the same person (‘same’ trials, 50%), or to different persons (‘different’ trials, 50%). In half of the trials the first stimulus in the pair represented the participant’s own hand or mobile phone (‘Self’ trials), whereas in the other half the first stimulus depicted hands or objects of another person (‘Other’ trials).

Single TMS pulses were randomly delivered at 300, 600 or 900 ms after the onset Meloxicam of the first picture; an earlier interval of 100 ms was also tested in a subgroup of subjects. The study was a 2 × 2 × 3 design with Stimuli (Hand, Mobile), Owner (Self, Other) and Interval (300, 600, 900 ms) as variables. The earlier interval (100 ms) was assessed separately (see below and Table 1). Each condition was repeated six times per block, for a total of 72 trials by block. Two blocks were presented in the same experimental session, for a total of 144 trials. The experimental conditions were fully randomized across trials. A short practice session of six trials was administered at the beginning of the session to familiarize participants with the task. The temporal structure of a representative trial is illustrated in Fig. 1. Each trial started with a central fixation cross displayed in the centre of the screen (1500 ms duration), followed by the sequential presentation of two images. The trial was timed-out by the participant’s response (up to 10 s).

As an index of corticospinal excitability, we recorded MEP amplitudes from an intrinsic muscle of the hand contralateral to the stimulated hemisphere. Larger MEPs following presentation of Self than Other hands in the right but not the left hemisphere would be taken as evidence of right hemispheric specialization for self body-parts processing. Twelve right-handed healthy participants (eight female; age range 24–36 years, mean 29 years) with no history of previous neurological or psychiatric disease participated in the experiment after providing informed consent. They were naïve as to the purpose of the study, which was approved by the INSERM Ethics Board

and run in accordance to the Declaration of Helsinki. Stimuli were colour pictures of participants’ left hand (see Fig. 1) and mobile phone. Epigenetics inhibitor Flash photographs were taken with a digital camera before the experimental session. Eleven subjects owned their mobile phone for more than 1 year, whereas one subject owned his mobile phone for 3 months. Pictures were taken in an indirectly illuminated environment while standing against a black uniform background. Images were

equalized for visual properties such a brightness and contrast and digitally edited with Adobe Photoshop to reduce any visual dissimilarity, such as brightness and contrast. MAPK Inhibitor Library clinical trial In each trial, two stimuli from the same category (e.g. two hands or two mobile phones, 50% of trials for each category) were successively presented, and could either belong to the same person (‘same’ trials, 50%), or to different persons (‘different’ trials, 50%). In half of the trials the first stimulus in the pair represented the participant’s own hand or mobile phone (‘Self’ trials), whereas in the other half the first stimulus depicted hands or objects of another person (‘Other’ trials).

Single TMS pulses were randomly delivered at 300, 600 or 900 ms after the onset acetylcholine of the first picture; an earlier interval of 100 ms was also tested in a subgroup of subjects. The study was a 2 × 2 × 3 design with Stimuli (Hand, Mobile), Owner (Self, Other) and Interval (300, 600, 900 ms) as variables. The earlier interval (100 ms) was assessed separately (see below and Table 1). Each condition was repeated six times per block, for a total of 72 trials by block. Two blocks were presented in the same experimental session, for a total of 144 trials. The experimental conditions were fully randomized across trials. A short practice session of six trials was administered at the beginning of the session to familiarize participants with the task. The temporal structure of a representative trial is illustrated in Fig. 1. Each trial started with a central fixation cross displayed in the centre of the screen (1500 ms duration), followed by the sequential presentation of two images. The trial was timed-out by the participant’s response (up to 10 s).

As an index of corticospinal excitability, we recorded MEP amplitudes from an intrinsic muscle of the hand contralateral to the stimulated hemisphere. Larger MEPs following presentation of Self than Other hands in the right but not the left hemisphere would be taken as evidence of right hemispheric specialization for self body-parts processing. Twelve right-handed healthy participants (eight female; age range 24–36 years, mean 29 years) with no history of previous neurological or psychiatric disease participated in the experiment after providing informed consent. They were naïve as to the purpose of the study, which was approved by the INSERM Ethics Board

and run in accordance to the Declaration of Helsinki. Stimuli were colour pictures of participants’ left hand (see Fig. 1) and mobile phone. Y-27632 mw Flash photographs were taken with a digital camera before the experimental session. Eleven subjects owned their mobile phone for more than 1 year, whereas one subject owned his mobile phone for 3 months. Pictures were taken in an indirectly illuminated environment while standing against a black uniform background. Images were

equalized for visual properties such a brightness and contrast and digitally edited with Adobe Photoshop to reduce any visual dissimilarity, such as brightness and contrast. Roxadustat In each trial, two stimuli from the same category (e.g. two hands or two mobile phones, 50% of trials for each category) were successively presented, and could either belong to the same person (‘same’ trials, 50%), or to different persons (‘different’ trials, 50%). In half of the trials the first stimulus in the pair represented the participant’s own hand or mobile phone (‘Self’ trials), whereas in the other half the first stimulus depicted hands or objects of another person (‘Other’ trials).

Single TMS pulses were randomly delivered at 300, 600 or 900 ms after the onset Teicoplanin of the first picture; an earlier interval of 100 ms was also tested in a subgroup of subjects. The study was a 2 × 2 × 3 design with Stimuli (Hand, Mobile), Owner (Self, Other) and Interval (300, 600, 900 ms) as variables. The earlier interval (100 ms) was assessed separately (see below and Table 1). Each condition was repeated six times per block, for a total of 72 trials by block. Two blocks were presented in the same experimental session, for a total of 144 trials. The experimental conditions were fully randomized across trials. A short practice session of six trials was administered at the beginning of the session to familiarize participants with the task. The temporal structure of a representative trial is illustrated in Fig. 1. Each trial started with a central fixation cross displayed in the centre of the screen (1500 ms duration), followed by the sequential presentation of two images. The trial was timed-out by the participant’s response (up to 10 s).

4). In KNO3-supplemented media, the wt strain showed gradual increase of biofilm up to 50 μM GSNO (Fig. 4). The addition of 50 μM GSNO to the Nap mutant restored the biofilm formation ability (Fig. 4). These data indicate the role of NO as an early signal Z-IETD-FMK order to induce formation of biofilm in A. brasilense. Neither lesser than 50 μM nor higher concentrations of GSNO restored the biofilm forming phenotype in the mutant strain, indicating that minor exogenous concentrations could be insufficient to trigger biofilm formation, and higher ones could be cytotoxic. The latter was corroborated by the diminished CFU mL−1 counts, where GSNO affected cell viability at 100 μM in KNO3-containing medium (data not

shown). On the other hand, in NH4Cl-containing medium, GSNO affects cell viability

only at 10 mM (data not shown). In natural environments, bacteria are often challenged by changing conditions, including different classes of nutrients availability, and various oxygen tensions (Danhorn & Fuqua, 2007). Some bacteria sense signals and environmental changes, and adjust their lifestyle from planktonic to sessile modes, triggering the formation of biofilms (Karatan & Watnick, 2009). Apart from providing different metabolic pathways, different N sources, NH4Cl or KNO3, generate different quantities of endogenous NO in A. brasilense Sp245 aerobic cultures (Molina-Favero et al., 2008). Therefore, we tested these two sources of N in the growing media in static conditions and concluded Atezolizumab clinical trial that there was a direct correlation between the presence of as a nitrogen source, and the quantity of biofilm formed (Fig. 2a and b). NO is a widespread intracellular and intercellular signaling molecule that regulates several functions that promote beneficial effects during the bacteria–plant interaction (Creus et al., 2005; Molina-Favero et al., 2008; Cohen et al., 2010). There are diverse reports on the function

Topoisomerase inhibitor of NO in biofilm formation. Schmidt et al. (2004) showed that treating N. europaea cultures with gaseous NO induced changes in growth characteristics, turning cells into nonmotile forms that produced biofilm on the reactor walls. Nevertheless, P. aeruginosa growing in aerobic conditions showed that a rise in the NO content in the preformed biofilm induced its dispersion and stimulated swarming motility (Barraud et al., 2006). This process occurred when the dominating conditions became anaerobic in the biofilm, inducing respiratory Nir activity. In addition, P. aeruginosa ΔnirS mutants, which produce less NO, showed a high degree of biofilm formation, while ΔNorCB mutants, which accumulate NO, showed an increased dispersion of the biofilm formed (Barraud et al., 2006). These results point to a different regulatory mechanism for biofilm formation or dispersion in ammonium-oxidizing bacteria and denitrifiers or pathogenic bacteria. Data presented in this paper could shed light on previous results obtained by Siuti et al.